1. Field of the Invention
The invention relates to ultrasonic transducers.
2. Description of Prior Art
The invention relates more particularly to such transducers for use in bonding tools for connecting semiconductors to printed circuit boards, for example. The bonding tools are used to apply pressure and ultrasonic energy simultaneously to miniature components. At present the materials used in the driver of the ultrasonic transducers are piezoelectric ceramics. The ceramic transducers have sharp resonances and high "Q". Within the narrow bandwidth of operation, coupling of different resonance modes causes a loss of energy to unwanted modes of vibration and reduces the efficiency as well as the stability of the transducer.